The present invention relates to an in-vehicle inverter device and an in-vehicle fluid machine.
Japanese Patent No. 5039515 discloses an in-vehicle inverter device that converts DC power into AC power. This in-vehicle inverter device has an inverter circuit having switching elements.
DC power to be converted by an in-vehicle inverter device may be contaminated by both of common mode noise and normal mode noise. In this case, these noises may hinder normal power conversion by the in-vehicle inverter device.
In an inverter circuit, for example, switching actions by switching elements or the like can generate noise. If the noise leaks out of the in-vehicle inverter device, it may adversely affect other in-vehicle devices connected to the in-vehicle inverter device.
In particular, since the specifications of the in-vehicle devices connected to the in-vehicle inverter device differ depending on the type of vehicle, the frequency band of undesirable noise may be different according to the type of vehicle. For this reason, in-vehicle inverter devices are sometimes desired to suppress leakage of noise in a wide frequency band so that the devices can be applied to various types of vehicles.
In an in-vehicle inverter device, one or more of unintended resonance circuits may be formed due to parasitic capacitance or the like. In this case, noise of a frequency close to the resonance frequency of the above-mentioned unintended resonance circuit may increase in amplitude. If the frequency band of noise for which leakage is desired to be suppressed is widened to improve the versatility as described above, a resonance frequency may be included in that frequency band, so that leakage of noise at frequencies close to the resonance frequency may not be sufficiently suppressed.